kg4ygb, Okay I do not know what year yours is so I am giving info based on my 05 2.8 CRD. First the glow plugs are accessed from under the intake manifold and the cac hose, flow meter and elbow usually are removed to access the #3 glow plug (not the normal job for a quick oil change establishment). The Fuel Quantity Solenoid is located on the upper engine side of the fuel pump on the forward driver's side of the engine and thus replacing the glow plugs would cause someone to be messing with the wires in that area. The 107, 101 and 102 codes all deal with the MAF sensor on top of the air filter housing. I just got both the 101 and 102 codes after cleaning the MAF sensor and then unplugging it. The MAF Sensor should be cleaned using the appropriate MAF cleaner, as oil such as K&N filter oil or from other source can cause running problems and cleaning with Brake or Carb Cleaner may or may not cause other issues or damage depending on who you speak with.
The boost pressure / air temp sensor, commonly referred to as the MAP sensor is located on top of the intake again on the drivers side of the engine and can cause a P0299 code. I would start by cleaning those censors, unplugging and plugging in the effected connectors and clear the codes to see if they return. I got some codes after my cleaning and test drive that did not return after the initial test drive when they were cleared. After you do all that kick the front left tire real hard and have 10 friends help you pick it up and shake it even harder and keep your fingers crosssed!!!
